Merge pull request #159 from miniway/master

Add zmq_proxy support for libzmq 3.2.2
Clean up build process
Add maven-gpg-plugin so we can sign builds
[maven-release-plugin] prepare release v2.1.0
[maven-release-plugin] prepare for next development iteration
First attempt at Travis-ci
Skip gpg signing
Merge pull request #160 from trevorbernard/travis-ci

Travis-ci
Add travis-ci status image
Add javadocs link in the README

[ci skip]
Fix #161 - send throws an exception if the socket is closed
Merge pull request #162 from trevorbernard/closed-socket-crash

Fix #161 - send throws an exception if the socket is closed
Replace 0MQ with ØMQ

[ci skip]
rewrite poller and zloop support
expose ZFrame.send as public

add ZFrame.print for debuggin